org.qbroker.common

Class CachedList

java.lang.Object

org.qbroker.common.AssetList

org.qbroker.common.CachedList

public class CachedList
extends AssetList

CachedList is an AssetList with cache and classification support. Each asset consists of a well-defined (not null) object and its MedaData, as well as a Perl5 Pattern for classifications. All assets in the list are indexed and can also be identified by their unique keys. CachedList also maintains a internal cache for dynamic topics. A topic is a text to be classified via the pattern match. The classification process will associate a topic to a number of assets if their patterns match the text. In fact, CachedList is an AssetList of objects and a QuickCache of topics plus Patterns for classifications.

Author:

yannanlu@yahoo.com

Constructor Summary

Constructors

Constructor and Description
CachedList(java.lang.String name, int capacity)
CachedList(java.lang.String name, int capacity, int option, int timeout, int threshold)

Method Summary

Modifier and Type	Method and Description
int	add(java.lang.String key, long[] meta, java.lang.Object obj) overrides the default behavior and adds a null as the pattern
int	add(java.lang.String key, long[] meta, java.lang.Object obj, int id) overrides the default behavior and adds a null as the pattern
int	add(java.lang.String key, long[] meta, org.apache.oro.text.regex.Pattern pattern, java.lang.Object obj) It checks object and the existence of the key first.
int	add(java.lang.String key, long[] meta, org.apache.oro.text.regex.Pattern pattern, java.lang.Object obj, int id) It checks object and the existence of the key first.
Browser	browser(java.lang.String topic, long currentTime) returns a Browser for all asset IDs associated with the topic or null if the topic does not exist or has expired by the time.
void	clear()
boolean	containsTopic(java.lang.String topic) It only checks the existence of the topic no matter whether it has expired or not.
java.lang.String[]	disfragment(long currentTime) It removes all expired topics, resets all sequence numbers and updates topic counts for each associated asset.
int	expire(java.lang.String topic, long currentTime) It expires the topic and returns 0 if the ttl is larger than zero.
protected void	finalize()
long	getCount(java.lang.String topic) returns the access count of the topic.
org.apache.oro.text.regex.Pattern	getPattern(int id) It returns the pattern for the id-th asset
org.apache.oro.text.regex.Pattern	getPattern(java.lang.String key) It returns the pattern for the asset with the key
long	getTimestamp(java.lang.String topic) returns the timestamp of the topic.
int	getTopicCount() returns the total number of cached topics.
int	getTopicCount(int id) returns the number of cached topics associated to an given asset.
int	getTTL(java.lang.String topic) returns the ttl of the topic.
int	insert(java.lang.String key, long[] meta, java.lang.Object obj, int id) overrides the default behavior and inserts a null as the pattern
int	insert(java.lang.String key, long[] meta, org.apache.oro.text.regex.Pattern pattern, java.lang.Object obj, int id) It checks the object and the existence of the key first.
Browser	insertTopic(java.lang.String topic, long timestamp, int ttl, int[] meta) It checks the existence of the topic first.
boolean	isExpired(java.lang.String topic, long currentTime) It returns true if the topic has expired, or false otherwise.
java.lang.Object	remove(int id) It removes both the object of the id and its metadata.
java.lang.Object	remove(java.lang.String key) It removes both the object of the key and its metadata.
java.lang.String[]	sortedTopics() returns an array of all existing topics in the NATURAL order.
java.util.Set<java.lang.String>	topicSet() returns a Set for all cached topics no matter whether they have expired or not.
int	touch(java.lang.String topic, long timestamp) It updates mtime of the topic if it has not expired yet.
int	touch(java.lang.String topic, long timestamp, long currentTime) It updates mtime of the topic with a given reference time for expiration.
int	updateTopic(java.lang.String topic, long timestamp, int ttl, int[] meta) As long as the topic exists, it updates the timestamp, ttl and metadata no matter whether the topic has expired or not.

Methods inherited from class org.qbroker.common.AssetList

browser, containsKey, existsID, get, get, getCapacity, getID, getKey, getMetaData, getMetaData, getName, isFull, queryIDs, replaceKey, rotate, set, set, size, swap

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CachedList

public CachedList(java.lang.String name,
                  int capacity,
                  int option,
                  int timeout,
                  int threshold)

CachedList

public CachedList(java.lang.String name,
                  int capacity)

Method Detail

insertTopic

public Browser insertTopic(java.lang.String topic,
                           long timestamp,
                           int ttl,
                           int[] meta)

It checks the existence of the topic first. If the topic exists but has not expired yet, it just returns the existing browser of the asset list. Otherwise, the topic will be inserted with the timestamp and the ttl. Upon success, it returns a Browser for the list of assets, or null in case of bad topic. With the return Browser, it lists all the asset IDs that match the topic.

updateTopic

public int updateTopic(java.lang.String topic,
                       long timestamp,
                       int ttl,
                       int[] meta)

As long as the topic exists, it updates the timestamp, ttl and metadata no matter whether the topic has expired or not. It returns 0 for if the topic has not expired yet, or 1 if the topic has expired. If the topic does not exist, it just returns -1 for failure.

expire

public int expire(java.lang.String topic,
                  long currentTime)

It expires the topic and returns 0 if the ttl is larger than zero. For an evergreen topic, it just returns 1 with no changes to its state. If the topic does not exist, it returns -1. The expiration action will not modify any metadata.

touch

public int touch(java.lang.String topic,
                 long timestamp)

It updates mtime of the topic if it has not expired yet. It retruns 0 on success, or -1 if the topic is not found or 1 if the topic has expired already.

touch

public int touch(java.lang.String topic,
                 long timestamp,
                 long currentTime)

It updates mtime of the topic with a given reference time for expiration. It retruns 0 on success, or -1 if the topic is not found or 1 if the topic has expired already.

isExpired

public boolean isExpired(java.lang.String topic,
                         long currentTime)

It returns true if the topic has expired, or false otherwise. It throws IllegalArgumentException if the topic is not found.

containsTopic

public boolean containsTopic(java.lang.String topic)

It only checks the existence of the topic no matter whether it has expired or not.

getTopicCount

public int getTopicCount()

returns the total number of cached topics.

getTopicCount

public int getTopicCount(int id)

returns the number of cached topics associated to an given asset.

getTTL

public int getTTL(java.lang.String topic)

returns the ttl of the topic.

getTimestamp

public long getTimestamp(java.lang.String topic)

returns the timestamp of the topic.

getCount

public long getCount(java.lang.String topic)

returns the access count of the topic.

disfragment

public java.lang.String[] disfragment(long currentTime)

It removes all expired topics, resets all sequence numbers and updates topic counts for each associated asset. It returns an array of all expired topics that have been just removed.

sortedTopics

public java.lang.String[] sortedTopics()

returns an array of all existing topics in the NATURAL order.

topicSet

public java.util.Set<java.lang.String> topicSet()

returns a Set for all cached topics no matter whether they have expired or not.

add

public int add(java.lang.String key,
               long[] meta,
               org.apache.oro.text.regex.Pattern pattern,
               java.lang.Object obj)

It checks object and the existence of the key first. If no such key exists, it adds the object and the metadata to the list. It returns the unique ID upon success or -1 otherwise.

add

public int add(java.lang.String key,
               long[] meta,
               java.lang.Object obj)

overrides the default behavior and adds a null as the pattern

Overrides:

add in class AssetList

add

public int add(java.lang.String key,
               long[] meta,
               org.apache.oro.text.regex.Pattern pattern,
               java.lang.Object obj,
               int id)

It checks object and the existence of the key first. If no such key exists, it reserves the id-th cell from the list and adds the object and the metadata to the cell with the index of id. It returns the id upon success or -1 otherwise.

add

public int add(java.lang.String key,
               long[] meta,
               java.lang.Object obj,
               int id)

overrides the default behavior and adds a null as the pattern

Overrides:

add in class AssetList

insert

public int insert(java.lang.String key,
                  long[] meta,
                  org.apache.oro.text.regex.Pattern pattern,
                  java.lang.Object obj,
                  int id)

It checks the object and the existence of the key first. If no such key exists, it inserts the object and the metadata to the list right before the object with the id. It returns the unique ID upon success or -1 otherwise.

insert

public int insert(java.lang.String key,
                  long[] meta,
                  java.lang.Object obj,
                  int id)

overrides the default behavior and inserts a null as the pattern

Overrides:

insert in class AssetList

remove

public java.lang.Object remove(java.lang.String key)

It removes both the object of the key and its metadata. It also cleans up the list on all the cached topics. It returns the removed object upon success or null otherwise.

Overrides:

remove in class AssetList

remove

public java.lang.Object remove(int id)

It removes both the object of the id and its metadata. It also cleans up the list on all the cached topics. It returns the removed object upon success or null otherwise.

Overrides:

remove in class AssetList

getPattern

public org.apache.oro.text.regex.Pattern getPattern(int id)

It returns the pattern for the id-th asset

getPattern

public org.apache.oro.text.regex.Pattern getPattern(java.lang.String key)

It returns the pattern for the asset with the key

browser

public Browser browser(java.lang.String topic,
                       long currentTime)

returns a Browser for all asset IDs associated with the topic or null if the topic does not exist or has expired by the time.

clear

public void clear()

Overrides:

clear in class AssetList

finalize

protected void finalize()

Overrides:

finalize in class AssetList